Question

A bag is filled with green and blue marbles. There are 117 marbles in the bag. If there are 25 more green marbles than blue marbles, find the number of green marbles and the number of blue marbles in the bag.

Answer 1

g = b+25

b+g = 117
Now solve for b and g.

or, start with about half of each
58+59 = 117
But you want the numbers to differ by 25, not just 1.
So move (25-1)/2 = 12 in each direction
58-12 + 59+12 = 117